DAEWOO LACETTI 2004 Service Repair Manual

5A1 – 122IZF 4 HP 16 AUTOMATIC TRANSAXLE
DAEWOO V–121 BL4
RangePark/
Neutr
alRever
seD321
GearNR1st2nd3rd4th1st2nd3rd1st2nd1st
Solenoid Valve
1ONON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFF
Solenoid Valve
2ONONONOFFOFFOFFONOFFOFFONOFFON
Line Pressure
Control Sole-
noid Valve 3
(EDS 3)OFFOFFOFFONON/
OFFON/
OFFOFFONON/
OFFOFFONOFF
Line Pressure
Control Sole-
noid Valve 4
(EDS 4)ONOFFONONONOFFONONONONONON
Line Pressure
Control Sole-
noid Valve 5
(EDS 5)OFFOFFONONOFFOFFONONOFFONONON
Line Pressure
Control Sole-
noid Valve 6
(EDS 6)ONOFFONONONOFFONONONONONON
Brake BAAAAAAAA
Brake CH
Brake DH
Clutch EAAAAAA
Brake FHHHHHHH
Lock–up
ClutchA
A = Applied
H = Holding
ON = The solenoid is energized.
OFF = The solenoid is de–energized.
** = Manual Second–Third gear is only available above approximately 100 km/h (62 mph).
*** = Manual First–Second gear is only available above approximately 60 km/h (37 mph).
Note : Manual First–Third gear is also possible at high vehicle speed as a safety feature.
DIAGNOSTIC TROUBLE CODE(DTC) P0734
GEAR 4 INCORRECT RATIO
Circuit Description
The TCM uses transaxle input speed information and out-
put speed sensor to control line pressure, TCC apply and
release and transaxle shift patterns. This information is
also uses to calculate the appropriate operating gear ra-
tios and TCC slippage. Conditions for Setting the DTC.
Conditions for Setting The DTC
S Time since TCM reset is greater than 500 msec.
S Time since shift end is greater than 500 msec.S Transmission oil temperature is greater than –10°C
(14°F).
S System voltage is greater than 9 volts.
S No input speed error DTCs P0715, P0716, and
P0717.
S Output speed is greater than 256 rpm.
S Input speed is greater than 400 rpm.
S No gear shift active.
Action Taken When The DTC Sets
S The Malfunction Indicator Lamp(MIL) will illuminate.

ZF 4 HP 16 AUTOMATIC TRANSAXLE 5A1 – 123
DAEWOO V–121 BL4
S The TCM will record operating conditions at the
time the diagnostic fails. This information will be
stored in the Failure Records buffer.
S Adopt Emergency/ Substitute mode and constant
4th gear by hydraulic control.
S After ignition OFF/ON : 3rd gear by hydraulic con-
trol. Possible P, R and N also possible.
S High line pressure
Conditions for Clearing the MIL/DTCS The MIL will turn OFF when the malfunction has
not occurred after three–ignition cycle.
S A history DTC will clear after 40 consecutive warm
up cycles without a fault.
S Using a scan tool can clear history DTCs.
Diagnostic Aids
S Check for intermittent input speed sensor or output
speed sensor circuit problems.
S Check for possible incorrect calibration.
DTC P0734 – Gear 4 Incorrect Ratio
StepActionValue(s)YesNo
1Perform an On–Board Diagnostic (EOBD) System
Check.
Is the check completed?–Go to Step 2Go to ”On–
Board Diagnos-
tic System
Check”
2Visually inspect the transaxle cooling system for
fluid leaks.
Was condition found and corrected?–Go to Step 7Go to Step 3
3Has the transaxle fluid checking procedure been
performed?–Go to Step 4Go to Trans-
axle fluid check
procedures
41. Using the scan tool record each transaxle drive
range.
2. Drive the vehicle in transaxle gear ranges 1,2,3
and D with TP greater than 15% and vehicle
speed greater than 16km/h(10mph) for five
seconds.
Does commanded gear ratio match ranges as
shown?1st = 2.719
2nd = 1.487
3rd = 1.000
4th = 0.717Refer to Diag-
nostic AidsGo to Step 5
5Perform line pressure check.
Was the condition found and corrected?–Go to Step 7Go to Step 6
6Check for possible clutch slippage.
Was the condition found and corrected?–Go to Step 7–
71. After the repair, use a scan tool
clear info"
function and road test the vehicle.
2. Review the
DTC info".
Has the last test failed or is the current DTC dis-
played?Replace trans-
axle assemblyRepair verified
exit DTC chart

5A1 – 124IZF 4 HP 16 AUTOMATIC TRANSAXLE
DAEWOO V–121 BL4
RangePark/
Neutr
alRever
seD321
GearNR1st2nd3rd4th1st2nd3rd1st2nd1st
Solenoid Valve
1ONON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFF
Solenoid Valve
2ONONONOFFOFFOFFONOFFOFFONOFFON
Line Pressure
Control Sole-
noid Valve 3
(EDS 3)OFFOFFOFFONON/
OFFON/
OFFOFFONON/
OFFOFFONOFF
Line Pressure
Control Sole-
noid Valve 4
(EDS 4)ONOFFONONONOFFONONONONONON
Line Pressure
Control Sole-
noid Valve 5
(EDS 5)OFFOFFONONOFFOFFONONOFFONONON
Line Pressure
Control Sole-
noid Valve 6
(EDS 6)ONOFFONONONOFFONONONONONON
Brake BAAAAAAAA
Brake CH
Brake DH
Clutch EAAAAAA
Brake FHHHHHHH
Lock–up
ClutchA
A = Applied
H = Holding
ON = The solenoid is energized.
OFF = The solenoid is de–energized.
** = Manual Second–Third gear is only available above approximately 100 km/h (62 mph).
*** = Manual First–Second gear is only available above approximately 60 km/h (37 mph).
Note : Manual First–Third gear is also possible at high vehicle speed as a safety feature.
DIAGNOSTIC TROUBLE CODE(DTC) P0781
1–2 SHIFT MALFUNCTION
Circuit Description
The special feature of 4HP 16 Auto Transaxle is that it op-
erates without freewheels. Shifting between individual
gears takes place by means of overlapping clutch engage-
ment and release.
The advantage of overlap shifting are as follows:
–The transaxle can be of more compact design and
is lighter on account of the absence of freewheels
and the lower number of shift elements.–Lower drag losses, i.e. higher efficiency.
–Lower peak torque acting on the components and
driveline.
However, overlap shifting necessitates high–performance
hardware and software, and precision engine signals.
Conditions for Setting The DTC
S Transmission oil temperature is greater than –10°C
(14°F).
S Selector lever is not N(Neutral), P(Park) position.
S System voltage is greater than 9 volts.

ZF 4 HP 16 AUTOMATIC TRANSAXLE 5A1 – 125
DAEWOO V–121 BL4
S No input speed error DTCs P0715, P0716, and
P0717.
S Output speed is greater than 256 rpm.
S Input speed is greater than 400 rpm.
S 1–2 gear shift is active.
S Immediately after the above condition occurs.
Action Taken When The DTC Sets
S The Malfunction Indicator Lamp(MIL) will illuminate.
S The TCM will record operating conditions at the
time the diagnostic fails. This information will be
stored in the Failure Records buffer.
S Adopt Emergency/ Substitute mode and constant
1st gear.S Open lock up clutch.
Conditions for Clearing the MIL/DTC
S The MIL will turn OFF when the malfunction has
not occurred after three–ignition cycle.
S A history DTC will clear after 40 consecutive warm
up cycles without a fault.
S Using a scan tool can clear history DTCs.
Diagnostic Aids
S When DTC P0781 sets, the possible cause of fault
could be TCM.
DTC P0781 – 1–2 Shift Malfunction
StepActionValue(s)YesNo
1Perform an On–Board Diagnostic (EOBD) System
Check.
Is the check completed?–Go to Step 2Go to ”On–
Board Diagnos-
tic System
Check”
21. Install the scan tool.
2. Turn the ignition ON, with the engine OFF.
3. Start engine and allow it to warm up at idle.
4. Observe ”idle rpm, TPS” on the scan tool.
Was condition found and corrected?–Refer to ”En-
gine diagnostic
information”Go to Step 3
3Inspect ”ECM”. Refer to Section 1F, System Diagno-
sis, EOBD System Check.
Was a problem found?–Go to ”Section
1F, System
Diagnosis”Go to Step 4
41. Turn the ignition OFF.
2. Disconnect the TCM wiring connector.
3. Measure the voltage between terminal B3 and
B13 of the transaxle wiring connector.
4. Turn the ignition ON.
5. Measure the voltage between terminal C15 and
B13 of the transaxle wiring connector.
6. Measure the voltage between terminal C16 and
B13 of the transaxle wiring connector.
Is the voltage within the values shown?11–14VGo to Step 5Go to ”System
voltage low or
high”
5Replace the TCM.
Is the action complete?–Go to Step 6–
61. After the repair, use a scan tool ”clear info”
function and road test the vehicle.
2. Review the ”DTC info”.
Has the last test failed or is the current DTC dis-
played?–Replace the
transaxle as-
semblyRepair verified
exit DTC chart

5A1 – 126IZF 4 HP 16 AUTOMATIC TRANSAXLE
DAEWOO V–121 BL4
RangePark/
Neutr
alRever
seD321
GearNR1st2nd3rd4th1st2nd3rd1st2nd1st
Solenoid Valve
1ONON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFF
Solenoid Valve
2ONONONOFFOFFOFFONOFFOFFONOFFON
Line Pressure
Control Sole-
noid Valve 3
(EDS 3)OFFOFFOFFONON/
OFFON/
OFFOFFONON/
OFFOFFONOFF
Line Pressure
Control Sole-
noid Valve 4
(EDS 4)ONOFFONONONOFFONONONONONON
Line Pressure
Control Sole-
noid Valve 5
(EDS 5)OFFOFFONONOFFOFFONONOFFONONON
Line Pressure
Control Sole-
noid Valve 6
(EDS 6)ONOFFONONONOFFONONONONONON
Brake BAAAAAAAA
Brake CH
Brake DH
Clutch EAAAAAA
Brake FHHHHHHH
Lock–up
ClutchA
A = Applied
H = Holding
ON = The solenoid is energized.
OFF = The solenoid is de–energized.
** = Manual Second–Third gear is only available above approximately 100 km/h (62 mph).
*** = Manual First–Second gear is only available above approximately 60 km/h (37 mph).
Note : Manual First–Third gear is also possible at high vehicle speed as a safety feature.
DIAGNOSTIC TROUBLE CODE(DTC) P0782
2–3 SHIFT MALFUNCTION
Circuit Description
The special feature of 4HP 16 Auto Transaxle is that it op-
erates without freewheels. Shifting between individual
gears takes place by means of overlapping clutch engage-
ment and release.
The advantage of overlap shifting are as follows:
–The transaxle can be of more compact design and
is lighter on account of the absence of freewheels
and the lower number of shift elements.–Lower drag losses, i.e. higher efficiency.
–Lower peak torque acting on the components and
driveline.
However, overlap shifting necessitates high–performance
hardware and software, and precision engine signals.
Conditions for Setting The DTC
S Transmission oil temperature is greater than –10°C
(14°F).
S Selector lever is not N(Neutral), P(Park) position.
S System voltage is greater than 9 volts.

ZF 4 HP 16 AUTOMATIC TRANSAXLE 5A1 – 127
DAEWOO V–121 BL4
S No input speed error DTCs P0715, P0716, and
P0717.
S Output speed is greater than 256 rpm.
S Input speed is greater than 400 rpm.
S 2–3 gear shift is active.
S Immediately after the above condition occurs.
Action Taken When The DTC Sets
S The Malfunction Indicator Lamp(MIL) will illuminate.
S The TCM will record operating conditions at the
time the diagnostic fails. This information will be
stored in the Failure Records buffer.
S Adopt Emergency/ Substitute mode and constant
2nd gear.S Open lock up clutch.
Conditions for Clearing the MIL/DTC
S The MIL will turn OFF when the malfunction has
not occurred after three–ignition cycle.
S A history DTC will clear after 40 consecutive warm
up cycles without a fault.
S Using a scan tool can clear history DTCs.
Diagnostic Aids
S When DTC P0782 sets, the possible cause of fault
could be TCM.
DTC P0782 – 2–3 Shift Malfunction
StepActionValue(s)YesNo
1Perform an On–Board Diagnostic (EOBD) System
Check.
Is the check completed?–Go to Step 2Go to ”On–
Board Diagnos-
tic System
Check”
21. Install the scan tool.
2. Turn the ignition ON, with the engine OFF.
3. Start engine and allow it to warm up at idle.
4. Observe ”idle rpm, TPS and so on” the scan
tool.
Was condition found and corrected?–Refer to ”En-
gine diagnostic
information”Go to Step 3
3Inspect ”ECM”. Refer to Section 1F, System Diagno-
sis, EOBD System Check.
Was a problem found?–Go to ”Section
1F, System
Diagnosis”Go to Step 4
41. Turn the ignition OFF.
2. Disconnect the TCM wiring connector.
3. Measure the voltage between terminal B3 and
B13 of the transaxle wiring connector.
4. Turn the ignition ON.
5. Measure the voltage between terminal C15 and
B13 of the transaxle wiring connector.
6. Measure the voltage between terminal C16 and
B13 of the transaxle wiring connector.
Is the voltage within the values shown?11–14VGo to Step 5Go to ”System
voltage low or
high”
5Replace the TCM.
Is the action complete?–Go to Step 6–
61. After the repair, use a scan tool ”clear info”
function and road test the vehicle.
2. Review the ”DTC info”.
Has the last test failed or is the current DTC dis-
played?–Replace the
transaxle as-
semblyRepair verified
exit DTC chart

5A1 – 128IZF 4 HP 16 AUTOMATIC TRANSAXLE
DAEWOO V–121 BL4
RangePark/
Neutr
alRever
seD321
GearNR1st2nd3rd4th1st2nd3rd1st2nd1st
Solenoid Valve
1ONON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFF
Solenoid Valve
2ONONONOFFOFFOFFONOFFOFFONOFFON
Line Pressure
Control Sole-
noid Valve 3
(EDS 3)OFFOFFOFFONON/
OFFON/
OFFOFFONON/
OFFOFFONOFF
Line Pressure
Control Sole-
noid Valve 4
(EDS 4)ONOFFONONONOFFONONONONONON
Line Pressure
Control Sole-
noid Valve 5
(EDS 5)OFFOFFONONOFFOFFONONOFFONONON
Line Pressure
Control Sole-
noid Valve 6
(EDS 6)ONOFFONONONOFFONONONONONON
Brake BAAAAAAAA
Brake CH
Brake DH
Clutch EAAAAAA
Brake FHHHHHHH
Lock–up
ClutchA
A = Applied
H = Holding
ON = The solenoid is energized.
OFF = The solenoid is de–energized.
** = Manual Second–Third gear is only available above approximately 100 km/h (62 mph).
*** = Manual First–Second gear is only available above approximately 60 km/h (37 mph).
Note : Manual First–Third gear is also possible at high vehicle speed as a safety feature.
DIAGNOSTIC TROUBLE CODE(DTC) P0783
3–4 SHIFT MALFUNCTION
Circuit Description
The special feature of 4HP 16 Auto Transaxle is that it op-
erates without freewheels. Shifting between individual
gears takes place by means of overlapping clutch engage-
ment and release.
The advantage of overlap shifting are as follows:
–The transaxle can be of more compact design and
is lighter on account of the absence of freewheels
and the lower number of shift elements.–Lower drag losses, i.e. higher efficiency.
–Lower peak torque acting on the components and
driveline.
However, overlap shifting necessitates high–performance
hardware and software, and precision engine signals.
Conditions for Setting The DTC
S Transmission oil temperature is greater than –10°C
(14°F).
S Selector lever is not N(Neutral), P(Park) position.
S System voltage is greater than 9 volts.

ZF 4 HP 16 AUTOMATIC TRANSAXLE 5A1 – 129
DAEWOO V–121 BL4
S No input speed error DTCs P0715, P0716, and
P0717.
S Output speed is greater than 256 rpm.
S Input speed is greater than 400 rpm.
S 3–4 gear shift is active.
S Immediately after the above condition occurs.
Action Taken When The DTC Sets
S The Malfunction Indicator Lamp(MIL) will illuminate.
S The TCM will record operating conditions at the
time the diagnostic fails. This information will be
stored in the Failure Records buffer.
S Adopt Emergency/ Substitute mode and constant
3rd gear.S Open lock up clutch.
Conditions for Clearing the MIL/DTC
S The MIL will turn OFF when the malfunction has
not occurred after three–ignition cycle.
S A history DTC will clear after 40 consecutive warm
up cycles without a fault.
S Using a scan tool can clear history DTCs.
Diagnostic Aids
S When DTC P0783 sets, the possible cause of fault
could be T/M.
DTC P0783 – 3–4 Shift Malfunction
StepActionValue(s)YesNo
1Perform an On–Board Diagnostic (EOBD) System
Check.
Is the check completed?–Go to Step 2Go to ”On–
Board Diagnos-
tic System
Check”
21. Install the scan tool.
2. Turn the ignition ON, with the engine OFF.
3. Start engine and allow it to warm up at idle.
4. Observe ”idle rpm, TPS and so on” the scan
tool.
Was condition found and corrected?–Refer to ”En-
gine diagnostic
information”Go to Step 3
3Inspect ”ECM”. Refer to Section 1F, System Diagno-
sis, EOBD System Check.
Was a problem found?–Go to ”Section
1F, System
Diagnosis”Go to Step 4
41. Turn the ignition OFF.
2. Disconnect the TCM wiring connector.
3. Measure the voltage between terminal B3 and
B13 of the transaxle wiring connector.
4. Turn the ignition ON.
5. Measure the voltage between terminal C15 and
B13 of the transaxle wiring connector.
6. Measure the voltage between terminal C16 and
B13 of the transaxle wiring connector.
Is the voltage within the values shown?11–14VGo to Step 5Go to ”System
voltage low or
high”
5Replace the TCM.
Is the action complete?–Go to Step 6–
61. After the repair, use a scan tool ”clear info”
function and road test the vehicle.
2. Review the ”DTC info”.
Has the last test failed or is the current DTC dis-
played?–Replace the
transaxle as-
semblyRepair verified
exit DTC chart

5A1 – 130IZF 4 HP 16 AUTOMATIC TRANSAXLE
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE(DTC) P1604
DATA CHECK OF INTERNAL & EXTENDED RAM FAILED
Circuit Description
A normal function of the Transmission Control Module
(TCM) programming is to perform an internal check that
verifies the integrity of the RAM memory allocations.
The DTC P1604 sets when the Random Access
Memory(RAM) is not operating correctly when checked on
initialization. An area of RAM is failed a read/ write test.
Conditions for Setting The DTC
S An area of RAM is failed a read/ write test.
S System voltage is too high or too low.
S Transaxle input voltage is too high or too low.
S Immediately after the above condition occurs.
Action Taken When The DTC Sets
S The Malfunction Indicator Lamp(MIL) will illuminate.S The TCM will record operating conditions at the
time the diagnostic fails. This information will be
stored in the Failure Records buffer.
S Adopt Emergency/ Substitute mode and constant
4th gear by hydraulic control.
S After ignition OFF/ON : 3rd gear by hydraulic con-
trol. Possible P, R and N also possible.
S Power supply cut off to the EDS valve.
Conditions for Clearing the MIL/DTC
The MIL will turn OFF when the malfunction has not oc-
curred after three–ignition cycle.
A history DTC will clear after 40 consecutive warm up
cycles without a fault.
Using a scan tool can clear history DTCs.
Diagnostic Aids
S When DTC P1604 sets, the possible cause of fault
could be TCM.

ZF 4 HP 16 AUTOMATIC TRANSAXLE 5A1 – 131
DAEWOO V–121 BL4
DTC P1604 – Data Check Of Internal & Extended Ram Failed
StepActionValue(s)YesNo
1Perform an On–Board Diagnostic (EOBD) System
Check.
Is the check completed?–Go to Step 2Go to ”On–
Board Diagnos-
tic System
Check”
21. Install the scan tool.
2. Turn the ignition ON, with the engine OFF.
Does the scan tool display P1604?–Go to Step 3Go to ”Diag-
nostic Aids”
31. Turn the ignition OFF.
2. Replace the TCM.
Is the action complete?–Go to Step 4–
41. Using the scan tool, clear the DTC.
2. Road test the vehicle within the conditions for
setting this DTC as specified in the text.
Does the scan tool indicate that this diagnostic has
run and passed?–Go to Step 5Go to Step 2
51. Check if any DTC(s) are set.
2. Are any DTC(s) displayed that have not been
diagnosed?–Go to ”Applica-
ble DTC table”System OK